Work vehicles typically include internal combustion engines that require clean air for use within the combustion process. Since many work vehicles, such as tractors and other agricultural vehicles, operate in fields and other harvesting environments in which the ambient air contains large amounts of dust, plant material and other particulates, an air intake system having an effective filter assembly is required. For example, conventional filter assemblies for work vehicles typically include a vortex or cyclone pre-cleaner configured to separate large particulates from the intake air and a porous air filter downstream of the pre-cleaner to provide the final stage of filtering prior to delivering the air into the engine.
To prevent the air filter from clogging, the large particulates separated from the intake air by the pre-cleaner must be removed from the filter assembly. Typically, such particulates are removed from the filter assembly via an outlet duct using a vacuum generated by the exhaust flow from the engine. However, the vacuum generated by the exhaust flow is often insufficient to meet the performance requirements of the filter assembly, thereby causing the air filter to plug within a short period of time.
To address this issue, the use of an electric aspirator has been proposed as a means for generating a stronger vacuum to allow for effective removal of the particulates from the pre-cleaner. For example, international application number PCT/US13/58367 (Chlystek et al.), filed on Sep. 6, 2013 and entitled “Air Intake System for a Work Vehicle,” discloses an electric blower for aspirating the pre-cleaner, the disclosure of which is hereby incorporated by reference herein in its entirety for all purposes. Specifically, the electric blower and related system of Chlystek et al. provides a means for effectively removing particulates from the pre-cleaner while also decreasing the risk of damage to the electric blower's motor.
However, while such a system certainly provides numerous advantages, a need continues to exist for refinements and improvements to electrically aspirated air intake systems. For instance, current control methodologies require that the motor associated with the electric aspirator run at a constant speed that is selected to accommodate the most extreme conditions. As a result, a significant amount of energy is wasted by forcing the alternator to continuously produce the power necessary to run the aspirator at the fixed speed. Moreover, by running the electric aspirator at the same speed for all operating conditions, the aspirator often provides more aspiration than is needed, which can lead to more flow restriction within the system and can cause the restriction sensor(s) within the system to be prematurely activated.
Accordingly, an improved system and method for controlling an electric aspirator used within an air intake system of a work vehicle would be welcomed in the technology.